Cartridge filters are well known to those skilled in the art of cleaning fluids used in industrial operations, such as a water purification plant, a completion or workover operation of a subterranean well, chemical process requiring recovery of a catalyst, refinery and chemical manufacturing operations or similar. Cartridge filters for disposable use are generally made of filter media that is fiber or paper-like substance and are designed to be received within a vessel housing same and are removed, disposed of, and replaced with new filters as needed. In industrial operations wherein a fluid, such as water or the like, is to be cleaned of particulate matter or a catalyst, such as fine sand, silt, catalyst fines, and other similar solids, which is deemed to be a contaminate or recoverable product for one reason or another. Other filter cartridges are made of a variety of media including metal, polymer or a combination of different filter media and can be used depending on the desired processing. These filters can become clogged in a similar manner to disposable cartridges.
When fluids associated with such industrial operations are cleaned incorporating such cartridge filters, a filter cake formed of said particulate or recoverable matter can be expected to accumulate around the exterior surface of the cartridge filter when the flow is from exterior to interior, and in some cases, the particulate matter will penetrate into the filter media itself, reducing the effectiveness of the cleaning operation and the rate of flow of fluid therethrough and otherwise adversely affecting the filtering operation. As a result of the clogging of the filter media, the cartridge filters must be cleaned or replaced from time to time. Such cleaning or replacement is often time consuming and otherwise costly, resulting in considerable downtime for the flow of fluid during the industrial operation.
Also, in some operations such as precious metals processing, catalyst recovery or other processing, the particulate matter in the fluid is valuable. A practical way to recover the particulate matter is desired in addition to extending the life of the filter.
In the past, those skilled in the art have attempted to extend the useful life of such disposable cartridge filters by, for example, controlling the pressure of the flow through the filtering system to eliminate or greatly reduce any differential pressure across the cartridge filter exterior surface to avoid a buildup of such a non-porous filter cake. Typical of such procedures is that disclosed in U.S. Pat. No. 1,780,723, entitled “Control for Oil Filters”, U.S. Pat. No. 3,926,806, entitled “No-Bypass Filter System,” and U.S. Pat. No. 5,160,442, entitled “Method of cleaning a disposable cartridge filter.”